Two years prior to the Union assault on Petersburg, a Confederate engineer named Captain Charles Dimmock, designed a ten-mile line of fortifications consisting of 55 artillery batteries.

It was this line of trenches that nearly surrounded the city of Petersburg that helped Confederate forces hold off Union forces during their initial assault on Petersburg. For nine-and-a-half months, the Union army besieged the City forcing Confederate forces to dig in and defend Petersburg and Richmond. The forts were the strongholds of Petersburg's trench system, though the Confederate lines contained better constructed batteries and fortified salients than large forts.